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I want to check the EM pulse between 3HZ-3kHZ with N9041B UXA Signal Analyzer,it seemed the only antenna I can use is Aaronia MagnoTRACKER,but the price is not affordable.

enter image description here

Then I plan to make ELF-ULF antenna myself,could you pls give me some thought to start with?

Mike Waters
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kittygirl
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    Sounds like an XY problem. The antenna cost is a rounding error on the N9041B analyser. What signals are you hoping to receive - natural background from the earth and sun, or artificial signals, like a mine rescue system, etc? – tomnexus Sep 29 '21 at 15:27
  • Those two cylinders likely house ferrite loop antennas. – Mike Waters Sep 30 '21 at 13:50
  • @tomnexus,ELF-ULF natural background pulse. – kittygirl Oct 04 '21 at 21:20

2 Answers2

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Years ago I used a simulation like this one for the same purpose.

The antenna you refer to is a tuned antenna, so it is not wideband. The antenna that I made is a wideband, really flat response (conversion from field strength to output voltage is frequency-independent).

Conclusion: the difficulty is the design of the low-noise amplifier. Depending on what you want to measure (strong signal or low-level signal in the noise) you can use a ferroceptor with many windings and loaded with 50 Ohm (not sensitive but doing the job) up to a large loop antenna with a transformer and a low-noise amplifier.

When you are used to a simulator with noise analysis: the basic model added can help you with a quick start. F Sessinkenter image description here

Forgot to say: dimensions in meters.....

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If you need calibrated output then you probably won't be able to do it. That's why they are so expensive. It's like a \$20 SDR dongle versus a \$2,000 spectrum analyzer, with the most notable difference being that the spectrum analyzer is calibrated and tells you how much power is at each frequency. If you don't need calibrated output and just want to get a pretty good feel of what's there, then you should totally build your own antenna.

hobbs - KC2G
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Jack0220
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  • `$20 SDR dongle versus a $2,000 spectrum analyzer`,why SDR dongle has less accuracy with less components? – WhiteGirl Feb 11 '22 at 13:03
  • The SDR looks at many frequencies at the same time and does some math on it, the spectrum analyzer only looks at one frequency at a time and does a very accurate power measurement on it, so it scans all the frequencies and plots the power. It is built for that purpose whereas the SDR is more for listening for stuff. Spectrum analyzer you're supposed to send it in every few years to recalibrate, but SDR nobody cares. – Jack0220 Jun 22 '22 at 15:48